Introduction

Shelf Life

Food preserving helped make it possible for our nomadic ancestors to settle down in one place and build agrarian communities where they could live in reasonable confidence that they would not go hungry through the variable seasons and the many other difficulties that nature might throw at them. Food preserving also made it possible for some of our ancestors to travel, taking their food with them as they journeyed over long distances to explore unknown places, confident, if they could find no fresh food, that their portable provisions meant they would not starve.

Preserved foods have played a significant role in our social and cultural history, and it is arguable that without the ability to preserve food, man might have been forced to continue his wanderings as a hunter-gatherer, following migrating herds and foraging for seasonal foods. A preserved harvest to feed people through the winter also allowed the slow evolution of the social and cultural complexities that owning and storing secure stocks of food and having long periods of seasonal leisure brought in their train. It encouraged the growth not only of arts and technologies, but also of social stratification, slavery, and endemic warfare. Without preserved food man might not have been able to send out large armies and naval ships to explore new lands and seas and conquer new territories. There might have been no great expeditions into the unknown, no great discoveries of navigation and science by men such as Vasco da Gama, Magellan, Drake, and Livingstone. There might have been no creation of the trade routes along which knowledge and culture were exchanged. The Poles might have remained unreached, rivers uncharted, mountains unscaled, and the moon unvisited. None of the greatest achievements in travel, exploration, and survival could have been possible without the increasing ability to preserve and carry food into places where none was available. Even now, men and women still take up impossible-sounding challenges to cross oceans, deserts, and ice, and still plan to live on preserved provisions, albeit using the latest in science, technology, and nutritional knowledge.

Few people in the developed world have to worry about hunger anymore. Yet the first thing everyone does when a crisis looms is to rush out and panic buy, stockpiling great quantities of preserved foods. It is this same instinct that drove our ancestors to find ways to keep supplies of food ready for all eventualities throughout the year. But then, unlike in modern society, they spent a great deal of their time worrying about where the next meal was coming from and most of their energies in producing, storing, preserving, and cooking their food. Abundant autumn crops of fruits and nuts and great quantities of fresh young summer vegetables all seem to come at once, for this is nature's way of ensuring the successful reproduction of each species. Short of stuffing themselves in the summer and autumn and starving for the rest of the year, ancient peoples had to find some way of cheating nature and turning these gluts of good things into food that would be available for eating all the year round.

Though the severity of the climate might vary, at least the rhythm of the seasons was predictable. Our forebears also had to find ways to provide against less predictable disasters such as diseases that ravaged them, their crops, and their livestock. In some parts of the world they also had to suffer long periods of drought, flooding, freezing, or tropical heat and invasions from aggressors and scarcity of food during the long, dark years of war. For many people the threat of famine from any of these causes remains a grim reality.

In the small, isolated, self-sufficient communities around the ancient world, people began searching for ways to preserve life by preserving food. What they found, with their extraordinary ingenuity and powers of observation, was a variety of ways in which they could harness the elements and use the natural chemicals around them to halt the inevitable processes of food decay, even though they had no scientific way of explaining how or why something worked. They developed different methods by combining drying, salting, smoking, and fermenting. Each community evolved techniques best suited to their climate, their food supplies, and their particular needs and culture. In the northern regions, for example, where the harsh winters made it almost impossible to find fresh foods, the people dried their food in the cold arctic air, cured their bacons and hams in the smoke hole over the hearth, and, when they discovered salt, they pickled and fermented fish, meat, and vegetables. The nomads of North Africa and the Slavic regions, who had no place to store food but plenty of daily milk supplies from their traveling herds, found ways to keep it by drying it or fermenting it into yogurts and cheeses carried in bags slung from their saddles. In the Middle East, surplus catches of fish, meat, and fruits were laid out in the sands or on their rooftops to dry in the baking sun to keep for many months. The gradual discovery of the preserving powers of heat and cold, salts, sugar and spices, vinegars and alcohols, and, later, airtight seals and containers slowly transformed the way people ate and influenced their developing cultures and lifestyles.

Food preserving did not simply keep food safe for eating, it also changed the texture and taste of foods, sometimes in a way that seemed revolting to people not accustomed to it. In some African and South Pacific countries, the powerful high flavor of rotted, fermented foods was much appreciated. The use of different food-preserving techniques around the world helped form national cuisines and taste preferences. Scandinavian and Russian people love sour tastes, while in eastern Europe sharp vinegary tastes became popular. All over the world, poor people subsisting on dull, monotonous, cereal-based diets were able to make highly flavored preserved sauces, pickles, and relishes to pep up their meals. Preserving also rendered some foods more palatable and processed some inedible, even poisonous, plants into safe and digestible nourishment.

Preserving methods created interesting new kinds of foods that entered the traditional meals of different cultures: succulent smoked hams, spicy dried sausages, and sweet cured bacon; chewy dried fruit that seem to taste of sunshine; jams and marmalade and rich, sugared fruits and nuts. Milk was transformed into thick salted butter and hundreds of kinds of matured cheeses. Varieties of strong dry breads and biscuits were developed to eat with cheese and potted meats. Delicate gravlax, pink smoked salmon, and salt cod became ingredients for classic national dishes. The need to preserve food to survive may not now be so important, but the desire to eat the foods and enjoy the unique tastes that preserving has given us is as great as ever. As Alan Davidson wrote in his bookMediterranean Seafood, "Tastes once acquired are often retained when the reason for acquiring them has disappeared."

We know a lot about how people lived and ate and about their food-preserving traditions around the world from the many travelers who, over the years, were useful observers as well as themselves being consumers of preserved food -- men such as Herodotus, the Greek geographer and historian who in 460B.C.journeyed throughout Turkey, the Aegean, Egypt, and Persia, "never tiring of his interest in other men's customs, religions and techniques," including food preserving. The eighteenth-century Chinese magistrate Li Hua-nan traveled all over China talking to the local people about their food and cooking. He was especially interested in food-preserving methods and how they helped ward off starvation. The merchant Marco Polo traveled from Venice to the Chinese court of Kublai Khan in the thirteenth century, marveling at the strange new foods and exotic cuisine. Later came those with a more political agenda such as William Cobbett and Daniel Defoe. Men were not, of course, the only travelers. There were many women, equally famous for their wanderlust and derring-do, who traveled alone in far-flung places. The first known woman traveler to record her journey was Egeria, a devout Christian from Rome who traveled to the Holy Land inA.D.383. Many others followed, though the majority of those now famous were Victorian women -- Freya Stark, Gertrude Bell, Mary Kingsley, Marianne North, and Isabella Bird.

For travelers, food had to be light, compact, long lasting, and nutritious. Different cultures from all over the world have nourished their traveling compatriots with varieties of dried meat, dried bread or biscuit, dried fruits, and fermented dairy products. Sea travel presented much greater problems for people sailing out of sight of land with no possibility of replenishing provisions for many months. Storage space on wooden ships was limited and the conditions were often quite unsuitable for keeping foods.

Preserving large amounts of food quickly before it spoiled required the help and cooperation of everyone in the community. Until the eighteenth century, few households in northern countries had enough land to grow hay for winter fodder, and by November the farmers had traditionally slaughtered all but the best of their livestock, which they kept back for breeding in the following year. The butchered meat was salted into barrels, laid out to dry or hung up above the hearth to smoke. Neighbors visited each other to assist with the salting, the sausage making, with cutting the cabbage for sauerkraut, preparing the apples for cider making and with fruit drying, butter churning, and cheese making. In many cases, they pooled their produce to make communal preserves, producing great barrels of wine or giant cheeses to be stored in their cellars, or bundles of sun-dried fruits, peppers, and tomatoes, which they laid out on the roofs of their houses or hung out in the dry air like washing. Cooperative food preserving helped to strengthen the sense of community, and everyone went home with a bit of fresh food to eat and some to put by, their stomachs filled from a good traditional feast to celebrate the job well done. For most ordinary people in the world, these food habits changed very little until the demise of the old traditional food preserving cultures in the 1950s and 1960s. Yet when people are uprooted and forced to move as settlers or refugees to a new land, it is their food traditions, including their preserving methods, that they cling to and continue to celebrate in their new homes. This is especially true in the United States, where the numerous "ethnic" cultural communities are turning away from their initial assimilation as Americans and rediscovering a pride in the culture and cuisine of their origins.

Life for us in recent decades has moved and changed so fast that it is difficult to appreciate how slow progress in food development has been in the past. In describing the history of food and food preserving since prehistory, it is very easy to get lost in time. Great events in history certainly affected everyone's lives -- invaders, settlers, and travelers brought new kinds of food and influenced cooking and tastes, particularly among the wealthier households. But for the majority, the basic traditions of food supply and preserving did not greatly change for centuries, and so neither did their diet. Their cooking pots were filled, if they were lucky, with much the same unchanging ingredients, which varied only in type and quantity, as they struggled to survive through the unyielding seasons and natural or man-made calamities. Each family strove, in its own particular way, to preserve the products of the July orchard for the January larder. Every man's ambition was food for himself and his family; every woman's rule was "waste not, want not." For the vast majority of the population, wherever they lived, as rural peasants or urban workers, it was satisfaction enough if their bellies were filled.

Life could be greatly improved, however, if they managed to preserve for more than their own future needs. A surplus of preserved food could be kept by until there was enough to be taken to market to be sold or bartered for tools, pots, vital salt supplies, and other necessities. As populations increased and moved from the country to work in the towns and cities far from the main sources of fresh foods, the need to find foods that were cheap and plentiful and could travel well became even more pressing. Religious dietary laws in Europe forbidding the eating of meat on certain days resulted in a huge demand for fish in the towns and cities inland. Fish was very perishable and had to be preserved quickly. This led to a burgeoning trade in salted and pickled fish, which encouraged authorities to increase already crippling taxes on salt and sugar. Meat was often moved "on the hoof." But fresh meat was always very scarce and the rural poor rarely saw any meat apart from the few animals of their own that they kept to be salted, dried, or smoked at home in the autumn and winter months.

During the eighteenth and nineteenth centuries, some of the food supply problems arising from the move from an agrarian to an industrial society were eased by great improvements in agriculture and food production. New fertilizers gave higher crop yields and the introduction of mechanized farming, the production of winter fodder for livestock, and the development of industrialized food processing in mills, breweries, and food factories increased the availability of affordable food. The causes of dietary diseases such as scurvy, rickets, and beriberi were not then properly understood, but their association with a diet dominated by certain preserved foods was recognized. The British navy, in particular, which had doubled in size during the Napoleonic wars, was still suffering from its inability to deal with the problem of scurvy, its ignorance of vitamins, and its inefficient victualing with so much salt food and hardtack. Armed forces throughout Europe and the colonies were desperate for a solution.

Spurred on by these demands for change, scientists and inventors began to make great strides in understanding the biological causes of food deterioration, in improving people's diets, and in the creation of new methods of food preservation. The invention of heat processing and canned foods, which could be transported everywhere, kept almost indefinitely, and could feed rich and poor alike, changed food preserving forever. Refrigeration and freezing transformed the fishing and meat industries, and the ever wider ownership of fridges and freezers since the 1950s has meant a whole new range of foods could be preserved and stored in the home. Railways and faster shipping meant that both food and people could be transported quickly and more efficiently. New preserving methods meant that food could now be imported and exported in huge quantities, and the economies of a number of countries were transformed. If food could be satisfactorily preserved for long storage and freighting, it was now valuable for international trade.

By the 1930s food in Europe and America was becoming big business, and a vast new range of exotic, previously unknown foods began to appear in our shops. Despite the poverty and hunger of the 1930s, many people could begin to vary their diet more and to radically change their cooking and eating habits. The old traditional processes that had served so well and become part of the culture and daily life of communities all over the world gradually gave way to new industrialized food processing. This process is still continuing in many parts of the world, and irradiation and other methods of the future are still being tested and explored.

The word "preservative," along with "additive," has gotten itself a bad name in recent years. The developed world has become obsessed with healthy diets, organic foods, and the "sell-by date." Public fears of additives and preservatives, genetically modified crops and irradiation have sent many people back to so-called organically grown fresh products and to some of the old "natural" traditional methods of preserving from the past. In America, in particular, they are now adapting old ways to more convenient, modern techniques so they can enjoy the gourmet pleasures of "homemade" smoking, bottling, pickling, and jam making. This is partly out of a desire for foods with real taste and quality and partly from a wish to return to a simpler world where, despite the poverty, hardship, and simple diet, the food was at least home-produced and one knew where it came from, how it had been processed, and what was in it.

The science and technology of food production will continue to be of major concern. While science has enormously improved both the safety and quality of our food today, consumer fears about the introduction of new kinds of processing and packaging, particularly when it seems to profit the food industry rather than the consumer, continue to be voiced (though malpractice and food adulteration is an ancient problem that has worried people since classical times). But we should also always remember that throughout history food preserving has provided cheap, plentiful, and varied food supplies for a vast number of people where there had otherwise been hunger and malnutrition. We should be just as concerned about our capacity to feed every mouth in the world's continually exploding population. We are still a long way from achieving this, but food preserving will certainly continue to play a vital part.

Each climate needs what other climes produce,

And offers something to the general use;

No land but listens to the common call,

And in return receives supplies from all.

The general intercourse, and mutual aid,

Cheer what were else a universal shade.

-- WILLIAMCOWPER(1731-1800)

Nearly everything we eat today has been treated in some way or another in order to prolong its life as a safe, transportable, salable, and storable food. On returning from our local stores or supermarkets laden with our week's food supplies, we start by unpacking quantities of food that we have selected from the freezer cabinets. We will also put away tins of cooked vegetables, meat, tuna and sardines in oil, fruits in syrup, and concentrated soups. We might also have bought bottles of vegetables pickled in brine or vinegar, olives and sun-dried tomatoes in oil, sauces, and mayonnaise. We will "put up" on the shelves jars of chutney, jam, and marmalade, and into the store cupboard will go packets of dehydrated, extruded, or freeze-dried products such as soups, milk, vegetables, coffee, cocoa, tea, sauces, custards, and gravy, as well as cubes of concentrated stock and tomato paste in tubes. We will have stocked up with packets of dried pasta, rice, pulses, nuts, and dried fruits such as apricots, prunes, and raisins. We may even have bought fresh products such as meat, bread, milk, and butter that we will "preserve" for later consumption in our own fast freezers at home.

If we are fortunate we may also have visited a local delicatessen stocked with delicacies and specialties from many different countries that have been preserved in the old traditional ways, which offer real flavor and quality over the often rather bland and packaged convenience foods that we have put away in our freezers and cupboards. We can choose succulent and tasty luxuries such as Scottish smoked salmon, Italian dried salami, German smoked sausages, bloaters and kippers from Yarmouth, hams and olives from Spain, salted Baltic herrings, and English sweet cured bacon, French potted pâtés, and the best matured cheeses of England, France, and elsewhere. A cornucopia of delicious, exotic-sounding foods, beautifully preserved using modern methods to produce improved versions of the ancient flavors that were once the food of the poor rural peasant. Few people today really know what these old preserving traditions were, who practiced them, and how they worked. It seems a great shame, because the facts and the stories surrounding them are so fascinating:

An understanding of what food is and how cooking works does no violence to the art of cuisine, destroys no delightful mystery. Instead, the mystery expands from matters of expertise and taste to encompass the hidden patterns and wonderful coincidences of nature. How remarkable it is, when you come to think in such terms, that heat has such fortunate effects on the flavor and digestibility of plant and animal tissues, that roast and meringue are two different outcomes of the same process, that wheat proteins have just the right balance of properties to make raised bread possible, that bread, cheese and yogurt, beer and wine are all the result of controlled spoilage! Science can enrich our culinary experience by deepening its significance, by disclosing its connections with the rest of the world.

-- HAROLDMCGEE,On Food and Cooking:

The Science and Lore of the Kitchen(1991)

Everything we eat has itself lived as some form of either plant or animal life. As soon as it has been slaughtered or plucked from the stalk, branch, or soil, our food starts to deteriorate. Although not necessarily immediately harmful to us, this seriously affects its value as a nutritional or edible food. The food chain is competitive, and if we don't quickly take advantage of a food, something else will. Foods that benefit us are also very attractive to many of the millions of minute microorganisms that proliferate in water, air, and soil. Their significance was not properly understood until late in the nineteenth century when Louis Pasteur published his 1861 paper showing that microorganisms were everywhere in the air. He had drawn some air, taken from different places, through very fine guncotton filters. When the filters were later dissolved in a mixture of ether and alcohol, tiny spores were found. Pasteur then drew air through a guncotton plug into a flask containing a sterile infusion. When the plug, which was now full of the airborne spores, fell into the flask, the infusion rapidly became putrid. Pasteur had finally shown that putrefaction is caused by airborne microorganisms.

Until then, people had believed that decomposition was a spontaneous event caused, in some unexplained way, by exposure to air. This crucial mistake was to hamper the development of food-preserving techniques right up until the time of Pasteur's discovery. Microorganisms had in fact been seen but not understood much earlier. A Dutch optician Antonie van Leeuwenhoek saw what he described as "living animalcules" through his homemade microscope in 1665. In 1774, an Italian priest Lazza Spallanzani had tried to disprove the theory of spontaneous degeneration by destroying bacteria on foods by heating them in a sealed flask. But, in a pattern repeated throughout the history of food preservation, no one was really listening enough to make the right connections, and people continued successfully to preserve their food from decomposition using empirical and, on the whole, scientifically correct methods without feeling the need to understand why they worked.

Despite their inability to see or know about microorganisms, people had, since the earliest times, observed the results of their activity. They would have seen food rot, and they began to practice a variety of effective methods of cheating these unknown creatures of their feast, developing techniques best suited to their own particular environment, using the elements and natural chemicals available. Amazingly, they also discovered how to create favorable conditions for some microorganisms so that they were actually beneficial in preserving certain foodstuffs -- bacteria for yogurt (lactobacilli naturally present in milk) and yeasts (from the bloom of the grape) for bread, beer, and wine -- in a process broadly known as fermenting.

There are different kinds of microorganisms that decompose food but most need certain common conditions in which to grow successfully, namely a warm, moist environment held on the slightly acid side of neutral and a supply of oxygen. (There is, however, a class of bacteria called anaerobes, which grow in the absence of oxygen, and in food preserving these must be destroyed at all costs.Clostridium botulinum, the cause of botulism, is the best known of these and the most dangerous.) The aim of most preserving methods is to remove these conditions in order to either destroy or inhibit the offending microorganisms already in the food. It is also very important that microorganisms should be prevented from reentering the food after it has been processed. Effective packaging and storing of preserved foods is therefore also important.

A wide variety of techniques were developed to create an alien environment for harmful bacteria. Since there are few processes that can achieve the removal of all the bacteria-friendly conditions, people soon began combining the different methods, using a selection of natural elements and conserving media. Whatever people had was put to use, whether it be the heat of the sun, hot and cold winds, hot sands, cooling coils, fire and smoke, salts, sugars, spices, herbs, acids, oils, airtight containers, or beneficial yeasts.

The development of the art of preserving was most likely a long and slow journey of trial and error, and also of taste. The idea of using combinations of different processes such as drying, airtight packaging, and low temperature would have been adopted to produce a food that would survive better than that produced by just one method. The fact that they were often complementary or that one ingredient helped to counter the negative effects of another was perhaps also a lucky accident. Nevertheless, the ability of our ancestors to observe, adapt, and "cheat" nature never ceases to astonish.

Excerpted from Pickled, Potted, and Canned: How the Art and Science of Food Preserving Changed the World by Sue Shephard
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